To visualize a power grid with several dozens or even hundreds of power lines and electrical power transmission control stations such as power converter stations and substations has been traditionally difficult from the human operator's point of view. So far only trivial visualization methods have been available. Such methods scale up poorly in visual terms and the operator gets lost in details when hundreds of individual stations and power lines are shown, which draw the operator's attention to each of them individually. Therefore, it is difficult to see the big picture as an overview of the power grid.
The fundamental challenge in visualization of power grids is to find a good balance between the amount and accuracy of information and its visual representation to an operator of an operator terminal, where the operator terminal is part of a supervisory control system to supervise, monitor and control the power grid. Such supervisory control system is also known under the term SCADA (Supervisory Control And Data Acquisition). As shown in FIG. 1, which shows an overview of a global power transmission system in the United States, display of individual power lines and stations of a power grid may result in too much information. Furthermore, if the transmission flow on the power lines is display using animated arrows, an overview would be obtained where there is much motion on the screen that draws the operator's eye equally to all power lines. This problem is usually avoided by adding layers that hide or show different types of power lines. Still, it is difficult to see the larger trends of e.g. transmission flow.
In power transmission or distribution systems, there may exist a large amount of system related data. Today it is hard for an operator to discern the data that is of relevance to him or her and then especially if the amount of power lines and stations are great.
Known visualizing systems are for instance described in US 2006/0238364, which discloses a visualization system for monitoring performance data of an electrical power distribution network. Indicia representing transformers are provided on a map and colour coded for conveying performance data.
JP 200050531 describes presenting a power system in three dimensions. Here a node voltage is displayed using a column with a height representing the voltage. Reactive power is presented through a sphere.
JP2002095187 describes visualization of a power distribution system for display in a WWW browser.
US 2009/0055527 describes a system for specifying arbitrary nodes and identifying a section between them on a system diagram. Here a table has positional information of nodes and data regarding a span between them.
US 2005/0041026 describes providing a graphic display of an electrical distribution network. The network includes power stations and power lines. In the system network operation data in the form incidents occurring at locations within a network segment are presented.
However, none of these documents provide a satisfactory visualization technique, when there are a lot of power lines and control stations.
The present invention is directed towards improving on this situation.